Hexacyanoferrate (HCF)

Hexacyanoferrate refers to a class of inorganic coordination complexes composed of a central iron ion octahedrally coordinated by six cyanide ligands, commonly existing as ferrocyanide ([Fe(CN)6]4-) and ferricyanide ([Fe(CN)6]3-) [3, 7]. These ions are not traditional therapeutic targets such as receptors or enzymes; rather, they function as chemical reagents, redox mediators, and precursors to the drug Prussian Blue (ferric hexacyanoferrate) [1, 13]. In clinical practice, hexacyanoferrate is utilized in histopathology for Perls' Prussian blue staining to visualize ferric iron deposits, which is essential for diagnosing iron-overload disorders like hemochromatosis [1, 14]. The therapeutic application of hexacyanoferrate is realized through Prussian Blue, an FDA-approved treatment for internal contamination with radioactive cesium-137 or thallium poisoning [3, 13]. Prussian Blue works by sequestering these toxic cations within its crystal lattice in the gut, facilitating their elimination via feces [3]. In research and biotechnology, hexacyanoferrate ions are widely employed as electron transfer agents in electrochemical biosensors and as probes for studying trans-plasma membrane redox systems [7, 12].

Other names

FerrocyanideFerricyanideHexacyanoferrate(II)Hexacyanoferrate(III)Yellow prussiateRed prussiateHexacyanidoferrate

As the drug Prussian Blue, it acts via ion exchange in the gastrointestinal tract to bind thallium and cesium ions, preventing their reabsorption and enhancing fecal excretion [3, 13].